The presence of symptoms within 6 months after COVID-19: a single-center longitudinal study

Sex Differences in Long COVID

Importance

A substantial number of individuals worldwide experience long COVID, or post-COVID condition. Other postviral and autoimmune conditions have a female predominance, but whether the same is true for long COVID, especially within different subgroups, is uncertain.

Objective

To evaluate sex differences in the risk of developing long COVID among adults with SARS-CoV-2 infection.

Design, Setting, and Participants

This cohort study used data from the National Institutes of Health (NIH) Researching COVID to Enhance Recovery (RECOVER)-Adult cohort, which consists of individuals enrolled in and prospectively followed up at 83 sites in 33 US states plus Washington, DC, and Puerto Rico. Data were examined from all participants enrolled between October 29, 2021, and July 5, 2024, who had a qualifying study visit 6 months or more after their initial SARS-CoV-2 infection.

Exposure

Self-reported sex (male, female) assigned at birth.

Main Outcomes and Measures

Development of long COVID, measured using a self-reported symptom-based questionnaire and scoring guideline at the first study visit that occurred at least 6 months after infection. Propensity score matching was used to estimate risk ratios (RRs) and risk differences (95% CIs). The full model included demographic and clinical characteristics and social determinants of health, and the reduced model included only age, race, and ethnicity.

Results

Among 12 276 participants who had experienced SARS-CoV-2 infection (8969 [73%] female; mean [SD] age at infection, 46 [15] years), female sex was associated with higher risk of long COVID in the primary full (RR, 1.31; 95% CI, 1.06-1.62) and reduced (RR, 1.44; 95% CI, 1.17-1.77) models. This finding was observed across all age groups except 18 to 39 years (RR, 1.04; 95% CI, 0.72-1.49). Female sex was associated with significantly higher overall long COVID risk when the analysis was restricted to nonpregnant participants (RR, 1.50; 95%: CI, 1.27-1.77). Among participants aged 40 to 54 years, the risk ratio was 1.42 (95% CI, 0.99-2.03) in menopausal female participants and 1.45 (95% CI, 1.15-1.83) in nonmenopausal female participants compared with male participants.

Conclusions and Relevance

In this prospective cohort study of the NIH RECOVER-Adult cohort, female sex was associated with an increased risk of long COVID compared with male sex, and this association was age, pregnancy, and menopausal status dependent. These findings highlight the need to identify biological mechanisms contributing to sex specificity to facilitate risk stratification, targeted drug development, and improved management of long COVID.

Long COVID in Children and Adolescents: A Critical Review

(1) Background: Data on persisting symptoms after SARS-CoV-2 infection in children and adolescents are conflicting. Due to the absence of a clear pathophysiological correlate and a definitive diagnostic test, the diagnosis of Long COVID currently rests on consensus definitions only. This review aims to summarise the evidence regarding Long COVID in children and adolescents, incorporating the latest studies on this topic. (2) Methods: We designed a comprehensive search strategy to capture all relevant publications using Medline via the PubMed interface, with the initial literature search conducted in April 2023. To be included, publications had to present original data and include >50 participants with Long COVID symptoms aged between 0 and18 years. (3) Results: A total of 51 studies met the inclusion criteria, with most studies originating from Europe (n = 34; 66.7%), followed by the Americas (n = 8; 15.7%) and Asia (n = 7; 13.7%). Various study designs were employed, including retrospective, cross-sectional, prospective, or ambispective approaches. Study sizes varied significantly, with 18/51 studies having fewer than 500 participants. Many studies had methodological limitations: 23/51 (45.1%) studies did not include a control group without prior COVID-19 infection. Additionally, a considerable number of papers (33/51; 64.7%) did not include a clear definition of Long COVID. Other limitations included the lack of PCR- or serology-based confirmation of SARS-CoV-2 infection in the study group. Across different studies, there was high variability in the reported prevalence of Long COVID symptoms, ranging from 0.3% to 66.5%, with the majority of studies included in this review reporting prevalences of approximately 10-30%. Notably, the two studies with the highest prevalences also reported very high prevalences of Long COVID symptoms in the control group. There was a relatively consistent trend for Long COVID prevalence to decline substantially over time. The prevalence of Long COVID appeared to differ across different paediatric age groups, with teenagers being more commonly affected than younger children. Furthermore, data suggest that children and adolescents are less commonly affected by Long COVID compared to adults. In children and adolescents, Long COVID is associated with a very broad range of symptoms and signs affecting almost every organ system, with the respiratory, cardiovascular, and neuropsychiatric systems being most commonly affected. (4) Conclusions: The heterogeneity and limitations of published studies on Long COVID in children and adolescents complicate the interpretation of the existing data. Future studies should be rigorously designed to address unanswered questions regarding this complex disease.

Prevalence and characteristics in long COVID among adults with asthma in the United States

OBJECTIVE

The purpose of this study was to assess: (1) the prevalence of long COVID by asthma status, and (2) the characteristics associated with developing long COVID among adults with asthma in the United States.

METHODS

Data from the 2022 National Health Interview Survey were used. The prevalence of long COVID was reported and stratified by asthma status. The multivariable logistic regression model was conducted to identify the factors associated with developing long COVID.

RESULTS

In 2022, the overall prevalence of long COVID among U.S. adults was 6.9%. When stratified by asthma status, the prevalence of long COVID was 13.9% among adults with asthma, and 6.2% among adults without asthma. Among adults with asthma, certain characteristics, including age over 55 years, female sex, obesity, problems paying medical bills and a history of asthma attacks, were significantly associated with developing long COVID.

CONCLUSIONS

This study revealed that the prevalence of long COVID among adults with asthma was much higher than the general adult population in the United States. The limited validity of the collected information in this study should prompt caution when interpreting our findings. Further studies on the association between asthma and long COVID could be valuable for the clinical practice.

Incidence and risk factors of post COVID-19 syndrome: a Tunisian cohort study

BACKGROUND

It has become increasingly clear that SARS-CoV-2 infection can lead to persistent physical and mental health problems lasting weeks or months, requiring prolonged periods of clinical care and increasing the burden on the healthcare system. This phenomenon, known as post COVID-19 syndrome (PCS), is a relatively new condition, its incidence is still unclear and differs between studies.

OBJECTIVES

In this cohort study, we aimed to estimate the incidence of PCS and to identify its risk factors in the Tunisian population.

METHODS

This is a prospective cohort study that enrolled patients diagnosed with COVID-19 from the triage unit of the University Hospital of Monastir, Tunisia. between April 2021 and June 2022. Patients were contacted by phone for a follow-up evaluation of PCS 12- weeks after the diagnosis date.

RESULTS

A total of 1451 individuals diagnosed with COVID-19 during the study period, responded to the follow-up evaluation after 3 months. The incidence of PCS was found to be 44.03% (95% CI [41.47; 46.58]), with fatigue being the most common symptom (21.5%), followed by cognitive impairment (10.3%), including memory loss and difficulty concentrating. Multivariate analysis revealed that the main associated factors to PCS were female gender (RR = 1.54; CI95% [1.30 - 1.82]), pre-existing comorbidities (RR = 1.30; CI95% [1.10 - 1.52]), duration of acute COVID-19 illness (days) (RR = 1.02; CI95% [1.01 - 1.03]), hospitalization (RR = 1.27; CI95% [1.05 - 1.53]), number of COVID-19 episodes (RR = 1.46; CI 95% [1.28 - 1.67]) and patients having receive two or more doses of vaccine prior to COVID-19 infection (RR = 0.82; CI95% [0.70 - 0.96]).

CONCLUSION

Our study allowed to estimate the incidence and identify risk factors of PCS. Recognizing these factors could help to better understand the underlying mechanisms and guide interventions for prevention and management of this condition.

Burden of Long COVID-19 in a Cohort of Recovered COVID-19 Patients in Delhi, India

BACKGROUND

The long COVID phase is characterized by signs and symptoms persisting for at least three months after recovery from acute COVID-19 illness. There is limited data on comprehensive long-term clinical follow-up of COVID-19 patients.

AIMS

This study aims to explore the burden and symptomatology of long COVID syndrome and its association with various health parameters.

SETTINGS AND DESIGN

This prospective observational study was conducted in Delhi from May 2022 to March 2023.

METHODS AND MATERIAL

A total of 553 adult patients who had recovered from COVID-19 were enrolled in the study. A sociodemographic and clinical profile was obtained using validated questionnaires, along with an evaluation of biochemical parameters to assess the associated factors.

STATISTICAL ANALYSIS USED

Chi-square test, unpaired t-test, and bivariate regression analysis were applied using Statistical Product and Service Solutions (SPSS, version 28; IBM SPSS Statistics for Windows, Armonk, NY). A p value of <0.05 was considered significant.

RESULTS

A total of 252 patients (45.6%) had long COVID syndrome, which was significantly associated with the presence of any pre-existing comorbidity (OR=1.46 (1.02-2.09); p=0.039), previous history of hypertension (OR=1.82 (1.07-3.09); p=0.027), and vaccination against COVID-19 (OR=1.392 (1.171-1.656); p=0.003). The most common symptoms reported were persistent fatigue (33.3%) and persistent dry cough (28.5%). Patients with long COVID syndrome are also reported to have poorer sleep quality. Biochemical findings showed abnormal T lymphocytes (9.3%) and raised HbA1c (11.9%).

CONCLUSIONS

Multiple risk factors and symptoms associated with long COVID syndrome were identified in this study. Research efforts and knowledge regarding the pattern of illness will aid in long-term monitoring and development of interventional strategies and guidelines for the care of recovered COVID-19 patients.

Prevalence and determinants of post-COVID-19 syndrome among patients 6 months post-discharge from a teaching hospital in South India

Background

The coronavirus disease 2019 (COVID-19) infection has affected millions of people worldwide in the last 4 years. Among those infected, the long-term COVID-19 syndrome, in which symptoms of COVID-19 persist for a variable period, is posing new challenges to the health system, but few studies are available in India that examine the post-COVID-19 syndrome, that is, 6 months and beyond COVID-19 infection. This study aimed to find the prevalence and determinants of post-COVID-19 syndrome among patients 6 months and beyond their infection.

Methodology

This cross-sectional study was conducted among 300 patients who were admitted and discharged from Government Medical College, Thrissur, at least 6 months before with a diagnosis of COVID-19 infection. The data collection was performed using a semi-structured interview schedule through a telephonic interview. The analysis was performed using the Statistical Package for the Social Sciences (SPSS) software.

Results

21% of the patients studied had at least one persistent symptom at the end of 6 months, and 4.1% had more than one symptom. Among the symptoms persisting most commonly were fatigue (11%) and dyspnea (7.7%). Other than persisting symptoms, 21% of patients developed exertional dyspnea and 19% developed sleep disturbances during the 6 months after discharge. The factors that were associated with persistent symptoms in univariate analysis were increasing age, presence of chronic obstructive pulmonary disease (COPD), presence of chronic kidney disease (CKD), and admission to the intensive care unit (ICU).

Conclusion

The study concludes that one-fifth of the patients still suffer from post-COVID-19 syndrome even 6 months after the COVID-19 infection. Our health systems should be prepared for the long-term management of COVID-19-infected people and prepare policies for the same.

The effectiveness of COVID-19 vaccines to prevent long COVID symptoms: staggered cohort study of data from the UK, Spain, and Estonia

BACKGROUND

Although vaccines have proved effective to prevent severe COVID-19, their effect on preventing long-term symptoms is not yet fully understood. We aimed to evaluate the overall effect of vaccination to prevent long COVID symptoms and assess comparative effectiveness of the most used vaccines (ChAdOx1 and BNT162b2).

METHODS

We conducted a staggered cohort study using primary care records from the UK (Clinical Practice Research Datalink [CPRD] GOLD and AURUM), Catalonia, Spain (Information System for Research in Primary Care [SIDIAP]), and national health insurance claims from Estonia (CORIVA database). All adults who were registered for at least 180 days as of Jan 4, 2021 (the UK), Feb 20, 2021 (Spain), and Jan 28, 2021 (Estonia) comprised the source population. Vaccination status was used as a time-varying exposure, staggered by vaccine rollout period. Vaccinated people were further classified by vaccine brand according to their first dose received. The primary outcome definition of long COVID was defined as having at least one of 25 WHO-listed symptoms between 90 and 365 days after the date of a PCR-positive test or clinical diagnosis of COVID-19, with no history of that symptom 180 days before SARS-Cov-2 infection. Propensity score overlap weighting was applied separately for each cohort to minimise confounding. Sub-distribution hazard ratios (sHRs) were calculated to estimate vaccine effectiveness against long COVID, and empirically calibrated using negative control outcomes. Random effects meta-analyses across staggered cohorts were conducted to pool overall effect estimates.

FINDINGS

A total of 1 618 395 (CPRD GOLD), 5 729 800 (CPRD AURUM), 2 744 821 (SIDIAP), and 77 603 (CORIVA) vaccinated people and 1 640 371 (CPRD GOLD), 5 860 564 (CPRD AURUM), 2 588 518 (SIDIAP), and 302 267 (CORIVA) unvaccinated people were included. Compared with unvaccinated people, overall HRs for long COVID symptoms in people vaccinated with a first dose of any COVID-19 vaccine were 0·54 (95% CI 0·44-0·67) in CPRD GOLD, 0·48 (0·34-0·68) in CPRD AURUM, 0·71 (0·55-0·91) in SIDIAP, and 0·59 (0·40-0·87) in CORIVA. A slightly stronger preventative effect was seen for the first dose of BNT162b2 than for ChAdOx1 (sHR 0·85 [0·60-1·20] in CPRD GOLD and 0·84 [0·74-0·94] in CPRD AURUM).

INTERPRETATION

Vaccination against COVID-19 consistently reduced the risk of long COVID symptoms, which highlights the importance of vaccination to prevent persistent COVID-19 symptoms, particularly in adults.

FUNDING

National Institute for Health and Care Research.

Risk and protective factors for Long COVID in Brazilian adults (CUME Study)

Background

Most people recover from COVID-19, however, between 5 to 20% have experienced new, recurring, or continuous health problems four or more weeks after being infected, a phenomenon called Long COVID, and whose reasons for its manifestation are incipient. Our objective was to analyse the risk and protective factors for Long COVID in Brazilian adults participating in the CUME Study.

Methods

The CUME Study is a prospective cohort conducted with graduates from federal universities in the State of Minas Gerais, Brazil. In this study, 390 participants who answered the baseline questionnaire in 2016 and the third follow-up questionnaire in 2022 (which contained a block of questions about occurrence of COVID-19 and Long COVID) were included. The diagnosis of Long COVID was based on self-reporting of persistence of signs and symptoms of COVID-19 between 30 days and 6 months after remission of the disease. To estimate the risk and protective factors for Long COVID, a hierarchical multivariate statistical analysis was conducted using the Poisson regression technique.

Results

Long COVID was observed in 48.9% of the participants. The following characteristics were identified as risk factors for the outcome: female sex (RR = 1.56; 95% CI = 1.22-1.99); prior diagnosis of hypertension (RR = 1.46; 95% CI = 1.19-1.80); having contracted COVID-19 in the first (RR =1.38; 95% CI = 1.07-1.79) or in the second waves (RR = 1.33; 95% CI = 1.07-1.65) of the pandemic period; and having presented three or more signs and symptoms during the acute phase of COVID-19 (RR = 2.99; 95% CI = 1.08-8.24). On the other hand, having a doctoral/postdoctoral educational level (RR = 0.69; 95% CI = 0.50-0.94) was identified as a protective factor for the outcome.

Conclusion

Health system managers and healthcare professionals should be aware of the socioeconomic profile and disease history of patients who have had COVID-19 because women, people with a prior diagnosis of hypertension, and those who manifested multiple signs and symptoms of COVID-19 during the acute phase of the disease were at greater risk of developing Long COVID.

Impact of Pre-Infection COVID-19 Vaccination on the Incidence and Severity of Post-COVID Syndrome: A Systematic Review and Meta-Analysis

This systematic review critically evaluated the impact of a pre-infection COVID-19 vaccination on the incidence and severity of post-COVID-19 syndrome and aimed to assess the potential protective effect across different vaccines and patient demographics. This study hypothesized that vaccination before infection substantially reduces the risk and severity of post-COVID-19 syndrome. In October 2023, a comprehensive literature search was conducted across three databases, PubMed, Embase, and Scopus, focusing on studies published up to that date. Utilizing a wide array of keywords, the search strategy adhered to the PRISMA guidelines and was registered in the Open Science Framework. The inclusion criteria comprised studies focusing on patients with a breakthrough SARS-CoV-2 infection who developed post-COVID-19 syndrome. We included a total of 13 articles that met the inclusion criteria, analyzing more than 10 million patients with a mean age of 50.6 years, showing that the incidence of intensive care unit (ICU) admissions post-vaccination was as low as 2.4%, with a significant reduction in mortality risk (OR 0.66, 95% CI 0.58-0.74). The prevalence of post-COVID-19 syndrome symptoms was lower in vaccinated individuals (9.5%) compared to unvaccinated (14.6%), with a notable decrease in activity-limiting symptoms (adjusted OR 0.59, 95% CI 0.48-0.73). Vaccinated patients also showed a quicker recovery and return to work (HR 1.37, 95% CI 1.04-1.79). The pooled odds ratio of 0.77 indicates that vaccination is associated with a 23% reduction in the risk of developing post-COVID-19 syndrome (95% CI 0.75-0.79). Despite the protective effects observed, a substantial heterogeneity among the studies was noted. In conclusion, a pre-infection COVID-19 vaccination is associated with a significant reduction in the risk and severity of post-COVID-19 syndrome. However, the observed heterogeneity across studies suggests a need for further research with standardized methods to fully comprehend vaccine efficacy against long COVID.

Looking at the Data on Smoking and Post-COVID-19 Syndrome-A Literature Review

Long COVID is a recently described entity that is responsible for significant morbidity and that has consequences ranging from mild to life-threatening. The underlying mechanisms are not completely understood, and treatment options are currently limited, as existing data focus more on risk factors and predictors. Smoking has been reported as a risk factor for poor outcomes of acute SARS-CoV-2 infection and seems to also play a role in mediating post-COVID-19 symptoms. We aimed to review relevant work addressing the interaction between smoking and long COVID in order to characterize smoking's role as a risk factor and possibly identify new research directions. Methods: The PubMed/MEDLINE database was searched using the keywords 'smoking', 'long COVID', and 'post-acute COVID' to identify relevant English-language articles published up to October 2023. Results and conclusions: From the 374 initial hits, a total of 36 papers were deemed relevant to the aim of the review. There was significant variability concerning the ways in which tobacco usage was quantified and reported; still, there is compelling evidence linking smoking to an increased risk of developing manifestations of post-acute-COVID disease. Some clinical conditions, such as dyspnea, cardiovascular symptoms, and cognitive or mental-health impairment, seem to be relatively strongly associated with smoking, while the connection between smoking and upper-airway involvement seems less certain. The available data support recommending smoking cessation as a clinical tool for the prevention of long COVID.

The effectiveness of COVID-19 vaccine in the prevention of post-COVID conditions: a systematic literature review and meta-analysis of the latest research

Objective

We performed a systematic literature review and meta-analysis on the effectiveness of coronavirus disease 2019 (COVID-19) vaccination against post-COVID conditions (long COVID) among fully vaccinated individuals.

Design

Systematic literature review/meta-analysis.

Methods

We searched PubMed, Cumulative Index to Nursing and Allied Health, EMBASE, Cochrane Central Register of Controlled Trials, Scopus, and Web of Science from December 1, 2019, to June 2, 2023, for studies evaluating the COVID-19 vaccine effectiveness (VE) against post-COVID conditions among fully vaccinated individuals who received two doses of COVID-19 vaccine. A post-COVID condition was defined as any symptom that was present four or more weeks after COVID-19 infection. We calculated the pooled diagnostic odds ratio (DOR) (95% confidence interval) for post-COVID conditions between fully vaccinated and unvaccinated individuals. Vaccine effectiveness was estimated as 100% x (1-DOR).

Results

Thirty-two studies with 775,931 individuals evaluated the effect of vaccination on post-COVID conditions, of which, twenty-four studies were included in the meta-analysis. The pooled DOR for post-COVID conditions among fully vaccinated individuals was 0.680 (95% CI: 0.523-0.885) with an estimated VE of 32.0% (11.5%-47.7%). Vaccine effectiveness was 36.9% (23.1%-48.2%) among those who received two doses of COVID-19 vaccine before COVID-19 infection and 68.7% (64.7%-72.2%) among those who received three doses before COVID-19 infection. The stratified analysis demonstrated no protection against post-COVID conditions among those who received COVID-19 vaccination after COVID-19 infection.

Conclusions

Receiving a complete COVID-19 vaccination prior to contracting the virus resulted in a significant reduction in post-COVID conditions throughout the study period, including during the Omicron era. Vaccine effectiveness demonstrated an increase when supplementary doses were administered.

A systematic review of the evidence on the associations and safety of COVID-19 vaccination and post COVID-19 condition

Post COVID-19 condition (PCC) refers to persistent or recurring symptoms (>8 weeks) occurring ≤12 weeks following acute COVID-19. The objective of this systematic review was to assess the evidence on the risk of PCC with vaccination before or after COVID-19 or after developing PCC, and the safety of vaccination among those already experiencing PCC. A search was conducted up to 13 December 2022 and standard systematic review methodology was followed. Thirty-one observational studies were included. There is moderate confidence that two doses of vaccine given pre-infection reduced the odds of PCC (pooled OR (pOR) 0.67, 95% CI 0.60-0.74, I2 = 59.9%), but low confidence that one dose may not reduce the odds (pOR 0.64, 95% CI 0.31#x2013;1.31, I2 = 99.2%), and the evidence is very uncertain about the effect of three doses (pOR 0.45, 95% CI 0.10#x2013;1.99, I2 = 30.9%). One of three studies suggested vaccination shortly after COVID-19 may offer additional protection from developing PCC compared to unvaccinated individuals, but this evidence was very uncertain. For those with PCC, vaccination was not associated with worsening PCC symptoms (10 studies) and appears safe (3 studies), but it is unclear if vaccination may change established PCC symptoms.

Neurological and Psychiatric Manifestations of Long COVID-19 and Their [18F]FDG PET Findings: A Review

For more than two years, lingering sequalae of COVID-19 have been extensively investigated. Approximately 10% of individuals infected by COVID-19 have been found to experience long-term symptoms termed "long COVID-19". The neurological and psychiatric manifestations of long COVID-19 are of particular concern. While pathogenesis remains unclear, emerging imaging studies have begun to better elucidate certain pathological manifestation. Of specific interest is imaging with [18F]FDG PET which directly reflects cellular glycolysis often linked to metabolic and inflammatory processes. Seeking to understand the molecular basis of neurological features of long COVID-19, this review encompasses the most recent [18F]FDG PET literature in this area.

Risk Factors Associated With Post-COVID-19 Condition: A Systematic Review and Meta-analysis

Importance

Post-COVID-19 condition (PCC) is a complex heterogeneous disorder that has affected the lives of millions of people globally. Identification of potential risk factors to better understand who is at risk of developing PCC is important because it would allow for early and appropriate clinical support.

Objective

To evaluate the demographic characteristics and comorbidities that have been found to be associated with an increased risk of developing PCC.

Data sources

Medline and Embase databases were systematically searched from inception to December 5, 2022.

Study Selection

The meta-analysis included all published studies that investigated the risk factors and/or predictors of PCC in adult (≥18 years) patients.

Data Extraction and Synthesis

Odds ratios (ORs) for each risk factor were pooled from the selected studies. For each potential risk factor, the random-effects model was used to compare the risk of developing PCC between individuals with and without the risk factor. Data analyses were performed from December 5, 2022, to February 10, 2023.

Main Outcomes and Measures

The risk factors for PCC included patient age; sex; body mass index, calculated as weight in kilograms divided by height in meters squared; smoking status; comorbidities, including anxiety and/or depression, asthma, chronic kidney disease, chronic obstructive pulmonary disease, diabetes, immunosuppression, and ischemic heart disease; previous hospitalization or ICU (intensive care unit) admission with COVID-19; and previous vaccination against COVID-19.

Results

The initial search yielded 5334 records of which 255 articles underwent full-text evaluation, which identified 41 articles and a total of 860 783 patients that were included. The findings of the meta-analysis showed that female sex (OR, 1.56; 95% CI, 1.41-1.73), age (OR, 1.21; 95% CI, 1.11-1.33), high BMI (OR, 1.15; 95% CI, 1.08-1.23), and smoking (OR, 1.10; 95% CI, 1.07-1.13) were associated with an increased risk of developing PCC. In addition, the presence of comorbidities and previous hospitalization or ICU admission were found to be associated with high risk of PCC (OR, 2.48; 95% CI, 1.97-3.13 and OR, 2.37; 95% CI, 2.18-2.56, respectively). Patients who had been vaccinated against COVID-19 with 2 doses had a significantly lower risk of developing PCC compared with patients who were not vaccinated (OR, 0.57; 95% CI, 0.43-0.76).

Conclusions and Relevance

This systematic review and meta-analysis demonstrated that certain demographic characteristics (eg, age and sex), comorbidities, and severe COVID-19 were associated with an increased risk of PCC, whereas vaccination had a protective role against developing PCC sequelae. These findings may enable a better understanding of who may develop PCC and provide additional evidence for the benefits of vaccination.

Trial Registration

PROSPERO Identifier: CRD42022381002.

Post-COVID-19 syndrome and quality of life impairment in severe COVID-19 Mexican patients

Introduction

Post-COVID-19 syndrome (PCS) usually occurs 3 months after the onset of COVID-19 with a symptom duration of at least 2 months without an alternative diagnosis.

Objective

This study aimed to describe the prevalence, characteristics, and impact on the quality of life (QoL) of post-COVID-19 syndrome in patients with a history of hospitalization for COVID-19.

Materials and methods

We conducted a cross-sectional study. Patients who required hospitalization due to COVID-19 between March 2020 and October 2021 were invited to answer a PCS questionnaire and the EQ-5D instrument. A total of 246 patients were included: 187 (76%) met the definition of PCS and 54% were men, with a median age of 50 years (IQR 41-63).

Results

From 187 patients with PCS, the median time to symptom onset after hospital discharge was 1 day (IQR 1-20), and the median symptom duration was 150 days (IQR 90-225). A total of 27 different symptoms were reported; the most frequent were difficulty concentrating (81%), dyspnea (75%), arthralgia (71%), fatigue (68%), and hair loss (60%). Some symptoms, such as difficulty concentrating, arthralgia/myalgia, and hair loss, were more prevalent in women with PCS. Patients with PCS had a higher frequency of tobacco smoking (37 vs. 4%, p = 0.02) and increased severity of lung involvement in the initial chest tomography (75 vs. 58%, p = 0.01) than those without PCS. Patients with PCS were less likely to receive antivirals (15.5 vs. 27%, p = 0.04). No difference between ICU admission, mechanical ventilation, and length of hospital stay was found. Patients with PCS had a lower visual analog scale result for EQ-5D vs. those without (80 [IQR 70-90] vs. 89.5 [IQR 75-90], p = 0.05). All five QoL dimensions were affected in PCS patients, showing increased pain/discomfort (67 vs. 39%, p = < 0.001), difficulties in performing usual activities (39.2 vs. 20.3%, p = 0.03), and anxiety/depression (57.5 vs. 37%, p = 0.02).

Conclusion

PCS occurred in 76% of hospitalized patients with prolonged duration and QoL impairment. Neurological symptoms such as difficulty concentrating were the most frequent symptoms. Timely diagnostic and therapeutic interventions are required.

Protective effect of COVID-19 vaccination against long COVID syndrome: A systematic review and meta-analysis

BACKGROUND

The relationship between coronavirus disease 2019 (COVID-19) vaccination and long COVID has not been firmly established. We conducted a systematic review and meta-analysis to evaluate the association between COVID-19 vaccination and long COVID.

METHODS

PubMed and EMBASE databases were searched on September 2022 without language restrictions (CRD42022360399) to identify prospective trials and observational studies comparing patients with and without vaccination before severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infection. We also included studies reporting symptomatic changes of ongoing long COVID following vaccination among those with a history of SARS-CoV-2 infection. Odds ratios (ORs) for each outcome were synthesized using a random-effects model. Symptomatic changes after vaccination were synthesized by a one-group meta-analysis.

RESULTS

Six observational studies involving 536,291 unvaccinated and 84,603 vaccinated (before SARS-CoV-2 infection) patients (mean age, 41.2-66.6; female, 9.0-67.3%) and six observational studies involving 8,199 long COVID patients (mean age, 40.0 to 53.5; female, 22.2-85.9%) who received vaccination after SARS-CoV-2 infection were included. Two-dose vaccination was associated with a lower risk of long COVID compared to no vaccination (OR, 0.64; 95% confidence interval [CI], 0.45-0.92) and one-dose vaccination (OR, 0.60; 95% CI, 0.43-0.83). Two-dose vaccination compared to no vaccination was associated with a lower risk of persistent fatigue (OR, 0.62; 95% CI, 0.41-0.93) and pulmonary disorder (OR, 0.50; 95% CI, 0.47-0.52). Among those with ongoing long COVID symptoms, 54.4% (95% CI, 34.3-73.1%) did not report symptomatic changes following vaccination, while 20.3% (95% CI, 8.1-42.4%) experienced symptomatic improvement after two weeks to six months of COVID-19 vaccination.

CONCLUSIONS

COVID-19 vaccination before SARS-CoV-2 infection was associated with a lower risk of long COVID, while most of those with ongoing long COVID did not experience symptomatic changes following vaccination.

Comparison of Long COVID-19 Caused by Different SARS-CoV-2 Strains: A Systematic Review and Meta-Analysis

Although many studies of long COVID-19 were reported, there was a lack of systematic research which assessed the differences of long COVID-19 in regard to what unique SARS-CoV-2 strains caused it. As such, this systematic review and meta-analysis aims to evaluate the characteristics of long COVID-19 that is caused by different SARS-CoV-2 strains. We systematically searched the PubMed, EMBASE, and ScienceDirect databases in order to find cohort studies of long COVID-19 as defined by the WHO (Geneva, Switzerland). The main outcomes were in determining the percentages of long COVID-19 among patients who were infected with different SARS-CoV-2 strains. Further, this study was registered in PROSPERO (CRD42022339964). A total of 51 studies with 33,573 patients was included, of which three studies possessed the Alpha and Delta variants, and five studies possessed the Omicron variant. The highest pooled estimate of long COVID-19 was found in the CT abnormalities (60.5%; 95% CI: 40.4%, 80.6%) for the wild-type strain; fatigue (66.1%; 95% CI: 42.2%, 89.9%) for the Alpha variant; and ≥1 general symptoms (28.4%; 95% CI: 7.9%, 49.0%) for the Omicron variant. The pooled estimates of ≥1 general symptoms (65.8%; 95% CI: 47.7%, 83.9%) and fatigue were the highest symptoms found among patients infected with the Alpha variant, followed by the wild-type strain, and then the Omicron variant. The pooled estimate of myalgia was highest among patients infected with the Omicron variant (11.7%; 95%: 8.3%, 15.1%), compared with those infected with the wild-type strain (9.4%; 95%: 6.3%, 12.5%). The pooled estimate of sleep difficulty was lowest among the patients infected with the Delta variant (2.5%; 95%: 0.2%, 4.9%) when compared with those infected with the wild-type strain (24.5%; 95%: 17.5%, 31.5%) and the Omicron variant (18.7%; 95%: 1.0%, 36.5%). The findings of this study suggest that there is no significant difference between long COVID-19 that has been caused by different strains, except in certain general symptoms (i.e., in the Alpha or Omicron variant) and in sleep difficulty (i.e., the wild-type strain). In the context of the ongoing COVID-19 pandemic and its emerging variants, directing more attention to long COVID-19 that is caused by unique strains, as well as implementing targeted intervention measures to address it are vital.

Prevalence of Long-COVID Among Low-Income and Marginalized Groups: Evidence From Israel

Objective: To identify the socioeconomic and demographic factors associated with the prevalence of self-reported long-COVID symptoms. Method: We examined the association between acute-COVID (SARS-CoV-2) and long-COVID symptoms, by a cross-sectional analysis of data obtained on a prospective online-survey, conducted from November to December 2021 on a nationally-representative sample of the Israeli population (N = 2,246). Results: Findings suggest that there is a greater likelihood of experiencing long-COVID symptoms among low-income and among marginalized groups. After controlling for demographic and socioeconomic attributes, those who had moderate/severe acute-COVID were 1.3 (p < 0.05) times more likely to experience a long-term symptom and also reported more long-term symptoms (2.2 symptoms) than those who have not been infected (1.4 symptoms; p < 0.01). Among the low-income group, a larger gap in symptom count was found between those who had moderate/severe acute-COVID (3.3 symptoms) and those who had not been infected (1.8 symptoms, p < 0.05). Conclusion: Our findings highlight the importance of raising awareness of long-COVID among marginalized population groups, and to the therapeutic options available. Such efforts should be tailored and should consider the unique socioeconomic and cultural characteristics, as well as the preexisting low access to healthcare services among these groups.

Post-COVID-19 syndrome symptoms after mild and moderate SARS-CoV-2 infection

Background

Post-COVID-19 Syndrome (PCS) is characterized by residual symptoms following the initial recovery from severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infection. The prevalence of PCS is known to be the highest among severe and critical forms of the disease. However, the occurrence and risk factors for PCS after mild or moderate SARS-CoV-2 infection has not been extensively investigated.

Methods

Online and offline via both paper or mailed questionnaires distributed among Jordan collected between 1st and 21st August 2021, including a total number of 800 respondents, of whom 495 had previous mild to moderate COVID-19 infection. The Newcastle post-COVID syndrome Follow-up Screening Questionnaire was modified, translated, and used as a standard instrument for data collection regarding psychological, medical, and socio-economic symptoms post-infection. The primary outcome was the prevalence of PCS after mild to moderate COVID-19 in Jordan. Secondary outcome was the identification of PCS risk factors.

Results

The most common PCS symptom was mood disturbance followed by fatigue, anxiety, and myalgia. Female gender significantly increased the risk for multiple PCS symptoms. Age < 30 years was found to be an independent risk factor for myalgia (p = 0.001).

Conclusion

PCS is highly prevalent among COVID-19 survivors in Jordan, especially in females and patients with comorbidities. Planning physical and mental rehabilitation services is recommended for those patients with PCS symptoms after mild to moderate COVID-19 infection.

Effect of COVID-19 Vaccines on Reducing the Risk of Long COVID in the Real World: A Systematic Review and Meta-Analysis

The coronavirus disease 2019 (COVID-19) is still in a global pandemic state. Some studies have reported that COVID-19 vaccines had a protective effect against long COVID. However, the conclusions of the studies on the effect of COVID-19 vaccines on long COVID were not consistent. This study aimed to systematically review relevant studies in the real world, and performed a meta-analysis to explore the relationship between vaccination and long COVID. We systematically searched PubMed, Embase, Web of science, and ScienceDirect from inception to 19 September 2022. The PICO (P: patients; I: intervention; C: comparison; O: outcome) was as follows: patients diagnosed with COVID-19 (P); vaccination with COVID-19 vaccines (I); the patients were divided into vaccinated and unvaccinated groups (C); the outcomes were the occurrence of long COVID, as well as the various symptoms of long COVID (O). A fixed-effect model and random-effects model were chosen based on the heterogeneity between studies in order to pool the effect value. The results showed that the vaccinated group had a 29% lower risk of developing long COVID compared with the unvaccinated group (RR = 0.71, 95% CI: 0.58-0.87, p < 0.01). Compared with patients who were not vaccinated, vaccination showed its protective effect in patients vaccinated with two doses (RR = 0.83, 95% CI: 0.74-0.94, p < 0.01), but not one dose (RR = 0.83, 95% CI: 0.65-1.07, p = 0.14). In addition, vaccination was effective against long COVD in patients either vaccinated before SARS-CoV-2 infection/COVID-19 (RR = 0.82, 95% CI: 0.74-0.91, p < 0.01) or vaccinated after SARS-CoV-2 infection/COVID-19 (RR = 0.83, 95% CI: 0.74-0.92, p < 0.01). For long COVID symptoms, vaccination reduced the risk of cognitive dysfunction/symptoms, kidney diseases/problems, myalgia, and sleeping disorders/problems sleeping. Our study shows that COVID-19 vaccines had an effect on reducing the risk of long COVID in patients vaccinated before or after SARS-CoV-2 infection/COVID-19. We suggest that the vaccination rate should be improved as soon as possible, especially for a complete vaccination course. There should be more studies to explore the basic mechanisms of the protective effect of COVID-19 vaccines on long COVID in the future.